North of a small shack you can find a large ledge of rock. You can get on top of it from the eastern side. Behind some bushes and a couple of car tires you can find a briefcase sitting on a rock.
South-west of the Weapons Shop you can find a series of old and rusted traincars. Inside one them you can find a briefcase sitting behind some old barrels.
At the far south-western part of the region you can find an old, trashed bus near the road. There's a ladder on the side of the bus and climbing it you can find a briefcase on the roof.
South-west of the safehouse in the southern area you can find a briefcase; it's located on the opposite side of the river by a large tree hanging over the river. You can gain access a bit east from the tree where you'll find a rock you can jump onto (see smaller image).
There's a briefcase up in the church tower in Sefapane. At the tower you'll find a boarded up doorway - smash the boards and climb the two ladders and you'll find the briefcase at the top.
In the south-eastern corner of the region you can spot the smoke from a fire, coming from behind some rocks. Jump onto nearby rocks to reach the fire - next to it sits a briefcase.